32000 mile t 440 .big balancer so i assume cast crank runs good . Good for putting in a b body whats your thoughts
thanks

Some of the later MH have the small spark plugs with the special 452 heads and the cooling or steam holes that match the block and heads. The heads and blocks need to go together so if you have cracked heads and try and sub any other head that does not have the steam holes, they can get hot. I've had personal experience with two motors before I finally figured it out.

Wait a minute here.........You're saying that the 440 motor home engines have different machining or casting than other 440s? Are you sure you are not confusing some of the particulars of the industrial 413s?

The heads are a very well known non performance item. But I have built several motor home 440s, I have one stroked to 499 in my Cuda now, and have never even heard of an issue with the block mating up properly to any stock style heads. Including the Eddies I have on mine now.

A pic of the engine would help a lot. Some MH 440's were close to pass car engines, some had the special heads and water pump. A pic from the top front would tell the story.

my 77 MH engine in my 88 truck has the bullet nosed balencer/cast crank,452 heads,5/8" peanut spark plugs. runs great with a stock 727/3.91 sg

just swaped to 3.23 with a q-jet on an rpm intake. 13mpg 10mpg with 3.91sg but lots of

I am going to swap a whiplash cam in mine and go back to 3.91 for some T&T for a time slip.

well thats my plan anyways.

I will jump on another one if I get the chance. they are the last of the H/D stock smogger BB after all.

Yes they are different. I found out the hard way. I'm not sure when it started but the MH short block I bought was NOS from Mopar in the80's. It was cast on 6-17-76.I had it in a dodge truck to pull my travel trailer. I could not keep it off 220 and it would vapor lock on a hot Texas day. I had 906 heads on it. My bud had the same problem with his 77 MH block and 906 heads. I gave up on mine and put the 400 back in and sold the truck. I did not know this about heads at the time. My bud had a MH block with 906 heads and it would get 220 as well. He reblocked it and it worked great. The MH blocks have extra small holes drilled at the bottom of the head surface that correspond to the holes that are right beside the spark plug on a 452 head. I looked forever until I found a set to match my NOS block. I did not know that they were just 452 heads with extra holes drill in an X right above the spark plug. Earlier casting do not have enough material to drill these holes. They also use the smaller tapered seat spark plugs like Chevys do. MH take a special head gasket as well. They have provisions for these holes. It lets water or steam flow around the spark plug. I could see that if you had aluminum heads, it would not be a problem. They cool better anyway. If my motor was apart, I would take pictures to show you.

yes i would like to see the difference /hint short block no difference only heads

Sounds similar to the steam holes on the Hemis.

I am surprised that blocking them while all the other water holes function would cause a problem.

I tapped and plugged mine w/set screws. Mostly because it opens up head gasket options. Never gets past 190...